<template>
  <div class="login_container">
    <div class="login_box">
      <!-- 头像区域 -->
      <div class="avatar_box">
        <img src="../assets/logo.png" />
      </div>
      <!-- 表单区域 -->
      <el-form
        ref="loginFormRel"
        :model="loginform"
        :rules="loginFormRules"
        class="login_form"
      >
        <!-- <el-form-item label="用户名"> -->
        <el-form-item prop="username">
          <el-input
            v-model="loginform.username"
            prefix-icon="iconfont icon-user"
          ></el-input>
        </el-form-item>
        <!-- 密码 -->
        <el-form-item prop="password">
          <el-input
            v-model="loginform.password"
            type="password"
            prefix-icon="iconfont icon-lock_fill"
          ></el-input>
        </el-form-item>
        <!-- 按钮区域 -->
        <el-form-item class="btns">
          <el-button type="primary" @click="login">登录</el-button>
          <el-button type="info" @click="resetloginForm">重置</el-button>
        </el-form-item>
      </el-form>
    </div>
  </div>
</template>

<script>
export default {
  name: 'Login',
  data() {
    return {
      //这是登录数据表单的绑定对象
      loginform: {
        username: 'admin',
        password: '123456'
      },
      loginFormRules: {
        //验证用户名是否合法
        username: [
          { required: true, message: '请输入登录名称', trigger: 'change' },
          { min: 3, max: 5, message: '长度在 3 到 5 个字符', trigger: 'change' }
        ],
        //验证密码是否合法
        password: [
          { required: true, message: '请输入登录密码', trigger: 'blur' },
          { min: 6, max: 15, message: '长度在 6 到 15 个字符', trigger: 'blur' }
        ]
      }
    }
  },
  methods: {
    //点击重置按钮，重置登录表单
    resetloginForm: function() {
      // console.log(this)
      this.$refs.loginFormRel.resetFields()
    },
    login() {
      //表单预验证
      this.$refs.loginFormRel.validate(async value => {
        //console.log(valid)      // false/true
        if (!value) return //即value为false时不发起请求

        // const result = this.$http.post('login',this.loginform)
        // console.log(result)  //Promise--可用async、await后变成具体的响应对象↓

        //从返回的对象中，取出data重命名为res
        const { data: res } = await this.$http.post('login', this.loginform)
        console.log(res) //Promise
        if (res.meta.status != 200) return this.$message.error('登录失败')
        this.$message.success('登录成功')

        //1.将登录成功之后的token，保存到客户端的sessionStorage中
        //  1.1 项目中除了登录之外的其他API接口，必须在登录之后才能访问
        //  1.2 token 只应在当前网站打开期间有效，所以将token保存在dizssionStorage中
        window.sessionStorage.setItem('token', res.data.token)
        //2.通过编程式导航跳转到后台主页，路由地址是 /home
        this.$router.push('/home')
      })
    }
  }
}
</script>

<style lang="less" scoped>
/* scoped防止样式冲突 */
.login_container {
  background-color: #2b4b6b;
  height: 100%;
}
.login_box {
  width: 450px;
  height: 300px;
  background: #fff;
  border-radius: 10px;
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  .avatar_box {
    height: 130px;
    width: 130px;
    border: 1px solid #eee;
    border-radius: 50%;
    padding: 10px;
    box-shadow: 0 0 10px #ddd;
    position: absolute;
    left: 50%;
    transform: translate(-50%, -50%);
    background: white;
    img {
      height: 100%;
      width: 100%;
      border-radius: 50%;
      background: #eee;
    }
  }
}

.login_form {
  position: absolute;
  bottom: 0;
  width: 100%;
  padding: 0 20px;
  box-sizing: border-box;
}
.btns {
  display: flex;
  justify-content: flex-end;
}
</style>